Université de Strasbourg, CNRS, ISIS, Strasbourg, France.
Nature. 2019 May;569(7754):104-107. doi: 10.1038/s41586-019-1151-1. Epub 2019 May 1.
Life builds its molecules from carbon dioxide (CO) and breaks them back down again through the intermediacy of just five metabolites, which are the universal hubs of biochemistry. However, it is unclear how core biological metabolism began and why it uses the intermediates, reactions and pathways that it does. Here we describe a purely chemical reaction network promoted by ferrous iron, in which aqueous pyruvate and glyoxylate-two products of abiotic CO reduction-build up 9 of the 11 intermediates of the biological Krebs (or tricarboxylic acid) cycle, including all 5 universal metabolic precursors. The intermediates simultaneously break down to CO in a life-like regime that resembles biological anabolism and catabolism. Adding hydroxylamine and metallic iron into the system produces four biological amino acids in a manner that parallels biosynthesis. The observed network overlaps substantially with the Krebs and glyoxylate cycles, and may represent a prebiotic precursor to these core metabolic pathways.
生命从二氧化碳（CO）中构建其分子，并通过仅五种代谢物的中介将其再次分解，这些代谢物是生物化学的通用枢纽。然而，核心生物代谢是如何开始的，以及为什么它使用这些中间产物、反应和途径，目前还不清楚。在这里，我们描述了一个由亚铁促进的纯粹的化学反应网络，在这个网络中，水丙酮酸和乙醛酸——两种非生物 CO 还原的产物——构建了生物克雷布斯（或三羧酸）循环的 11 个中间产物中的 9 个，包括所有 5 个通用代谢前体。中间产物以类似于生物合成和分解代谢的生命样状态同时分解为 CO。向系统中添加羟胺和金属铁以类似于生物合成的方式产生四种生物氨基酸。观察到的网络与克雷布斯和乙醛酸循环有很大的重叠，可能代表这些核心代谢途径的前生物前体。
